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CASE REPORT
Beta-blocker stress echocardiography in an aortic stenosis patientwith associated left ventricular outflow tract obstruction
Masataka Sugahara • Akiko Goda • Mitsuru Masaki • Ayumi Nakabo •
Shohei Fujiwara • Miho Fukui • Kanako Itohara • Shinichi Hirotan •
Kazuo Komamura • Masaaki Kawabata-Lee • Takeshi Tsujino • Tohru Masuyama
Received: 11 December 2013 / Revised: 17 March 2014 / Accepted: 31 March 2014 / Published online: 16 April 2014
� Japanese Society of Echocardiography 2014
Abstract An 80-year-old man visited our hospital
because of dyspnea on exertion from 6 months ago. Echo
Doppler study showed severe calcification in the aortic
valve with restricted movement and the sigmoid septum
causing obstruction at the LV outflow tract (LVOT).
Considering the aortic valve area (AVA) might have been
inaccurately estimated, we carried out beta-blocker stress
echocardiography. The transaortic pressure gradient and
AVA were respectively calculated as 52 mmHg and 0.90
cm2 before propranolol administration and as 64 mmHg
and 0.86 cm2 after propranolol administration. Thus, beta-
blocker stress echocardiography may provide an accurate
assessment of AS if the LVOT obstruction is concomitant.
Keywords Aortic stenosis � Sigmoid septum � Echo
Doppler � Beta-blocker � Stress echocardiography
Case report
The patient was an 80-year-old man who visited our hos-
pital because of dyspnea on exertion from 6 months ago.
He was 167 cm tall and 53 kg (BSA = 1.59 m2). His
blood pressure was 138/70 mmHg. Echo Doppler study
showed LV hypertrophy with chamber dilatation and left
atrial dilatation. The LV ejection fraction was 66 %. The
aortic valves (AV) had severe calcification, and their
movement was restricted. There was a sigmoid septum at
the LV outflow tract (LVOT) with systolic anterior motion
of the mitral anterior leaflet. Continuous-wave Doppler
LVOT flow velocity was 2.5 m/s, and trans-aortic valve
flow velocity (VAV) was 4.4 m/s (Fig. 1). Because there
was an accelerated flow at LVOT due to dynamic subaortic
obstruction, the pressure gradient of the aortic valve
(DPAV) was estimated using the simplified Bernouli
equation: DPAV = 49(VAV)2 - 49(VLVOT)2 (mmHg),
where VLVOT stands for velocity at the LVOT. It was
52 mmHg, and the continuity equation-based aortic valve
area (AVA) was 0.90 cm2. Considering AVA might be
inaccurately estimated because of the associated dynamic
subaortic obstruction, we carried out drug stress echocar-
diography. Specifically, 2 mg propranolol was intrave-
nously administered to attenuate the subaortic stenosis. The
VLVOT and VAV decreased from 2.5 to 1.3 m/s and from 4.4
to 4.2 m/s, respectively, after intravenous injection of
propranolol. The DPAV and AVA were respectively cal-
culated as 52 mmHg and 0.90 cm2 before propranolol
administration and as 64 mmHg and 0.86 cm2 after pro-
pranolol administration (Fig. 2). Because we diagnosed the
AS as severe, the patient underwent aortic valve replace-
ment in a month.
Discussion
The number of elderly patients with degenerative AS has
been markedly increasing, and the value of echocardiog-
raphy as a standard technique for the assessment of AS is
particularly important in these patients [1]. The sigmoid
septum is frequently associated with AS in elderly patients
M. Sugahara � A. Goda � M. Masaki � A. Nakabo �S. Fujiwara � M. Fukui � K. Itohara � S. Hirotan �K. Komamura � M. Kawabata-Lee � T. Masuyama (&)
Cardiovascular Division, Department of Internal Medicine,
Hyogo College of Medicine, Nishinomiya, Hyogo, Japan
e-mail: [email protected]
T. Tsujino
Department of Pharmacy, School of Pharmacy, Hyogo
University of Health Science, Kobe, Japan
123
J Echocardiogr (2014) 12:68–70
DOI 10.1007/s12574-014-0212-6
h VAV 4.4 m/secΔP 52mmHgAVA 0.90cm2
f
a b
c d e
g VLVOT 2.5 m/sec
Fig. 1 Echo Doppler was performed on his admission. a Two-
dimensional echocardiogram of the left side parasternal long axis
view at end-diastole. b Two-dimensional echocardiogram of the left
side parasternal long axis view at end-systole. c Two-dimensional
echocardiogram of the left side parasternal long axis view showing
LVOT at end-diastole. d Two-dimensional echocardiogram of the left
side parasternal long axis view showing LVOT at mid-systole.
e M-mode echocardiogram showing systolic anterior motion of the
mitral anterior leaflet. f Color Doppler echocardiogram showing
accelerated LVOT flow. g Pulse-wave Doppler echocardiogram and
continuous-wave Doppler echocardiogram through the LVOT. h Con-
tinuous-wave Doppler echocardiogram through the aortic valve
a c VAV 4.2 m/sec ΔP 64mmHg AVA 0.86cm2
b VLVOT 1.3m/sec
Propranolol Administration Pre Post
BP (mmHg) 149/64 145/60
HR (bpm) 52 48
VLVOT (m/sec) 2.5 1.3
VAV (m/sec) 4.4 4.2
ΔP (mmHg) 52 64
AVA (cm2) 0.90 0.86
d
BP: Blood pressure HR: Heart rate LVOT : Le� ventricular ou�low tract VLVOT: Flow velocity through the LVOT VAV: Flow velocity through the aor�c valve ΔP: Pressure gradient between the LVOT and the ascending aorta AVA: Aor�c valve area
Fig. 2 We performed
propranolol stress
echocardiography. a Two-
dimensional echocardiogram of
the left side parasternal long
axis view showing LVOT.
b Pulse-wave Doppler
echocardiogram through the
LVOT. c Continuous-wave
Doppler echocardiogram
through the aortic valve
J Echocardiogr (2014) 12:68–70 69
123
simply because of the steady increase in sigmoidity of the
ventricular septum with aging [2]. A sigmoid septum fre-
quently causes an obstruction at the LVOT because of the
sharp angle between the mid-line axis of the ascending
aorta and that of the interventricular septum [2]. If suba-
ortic stenosis is associated with aortic stenosis, it is
unpredictable whether it will cause over- or underestima-
tion of DPAV in individual patients; thus, the best way
should be to decrease the degree of subaortic stenosis as
much as possible. Therefore, we attempted to normalize
VLVOT using a negative inotropic drug (propranolol). Beta-
blockers are an established treatment for LVOT obstruction
in HCM subjects [3]. For instance, intravenous landiolol
infusion attenuated LVOT obstruction caused by the sig-
moid septum on general anesthesia [4].
Although dobutamine and/or exercise stress is a popular
intervention to improve the accuracy of AS assessment,
such a stress was obviously inappropriate in this patient.
On the contrary, intervention with a negative inotropic
agent may be useful in such patients. Thus, beta-blocker
stress echocardiography may provide accurate assessment
of AS if the LVOT obstruction is concomitant.
Conflict of interest There are no financial or other relations that
could lead to a conflict of interest.
References
1. Baumgartner H, Hung J, Bermejo J, et al. Echocardiographic
assessment of valve stenosis: EAE/ASE recommendations for
clinical practice. J Am Soc Echocardiogr. 2009;22:1–23.
2. Toth AB, Engel JA, McManus AM, et al. Sigmoidity of the
ventricular septum revisited: progression in early adulthood,
predominance in men, and independence from cardiac mass. Am
J Cardiovasc Pathol. 1988;2:211–23.
3. Sherrid MV, Pearle G, Gunsburg DZ. Mechanism of benefit of
negative inotropes in obstructive hypertrophic cardiomyopathy.
Circulation. 1998;97:41–7.
4. Omae T, Tsuneyoshi I, Higashi A, et al. A short-acting beta-
blocker, landiolol, attenuates systolic anterior motion of the mitral
valve after mitral valve annuloplasty. J Anesth. 2008;22:286–9.
70 J Echocardiogr (2014) 12:68–70
123